College researchers wanted to know under what conditions people are more likely to complete and return a survey. As part of a study, the researchers prepared three sets of identical surveys and used three methods of delivering and returning the surveys. The methods are described as follows.
In Class: The surveys were given to students in a class, and students were asked to return completed surveys to their instructor.
Psychology: The surveys were given to students participating in a psychology experiment, and students were asked to return completed surveys to a collection box in the hallway of the psychology building.
Dining Hall: The surveys were given to students in the dining hall, and students were asked to return completed surveys to a collection box outside the dining hall.
The graph shows the percent of surveys returned and not returned for each delivery method.
Which statement about delivery method and rate of survey return is supported by the graph?
A
There is a positive association between delivery method and rate of return.
B
There is a negative association between delivery method and rate of return.
C
The number of surveys given using the Dining Hall delivery method was less than the number given using either of the other delivery methods.
D
The Psychology delivery method displays the most symmetric results; the other delivery methods display skewed results.
E
The In Class delivery method had the greatest rate of return, and the Dining Hall delivery method had the least rate of return.